VII. SITING AND ENVIRONMENTAL PROTECTION

the primary concerns are biochemical oxygen demand (BOD) and phenol concentrations found in water runoff and percolation (Lafrance et al., 1996; Richard and

Chadsey, 1994). BOD and phenols are both natural products of decomposition, but

the concentrated levels generated by large-scale composting dictate that runoff

should not be directly discharged into surface water. Additional potential concerns

when composting nutrient rich materials such as grass, manure, or biosolids include

N compounds such as nitrate (NO3) and NH3, and in some cases P as well. With

biosolids, manure, and even yard trimmings, there may also be pathogen concerns.

Although important, these concerns are readily managed, and can be mitigated

through careful facility design and operation.

A. Facility Design

Selecting the right site is critical to many aspects of a composting operation,

from materials transport and road access to neighborhood relations. From an environmental management perspective, the critical issues are soil type, slope, and the

nature of the buffer between the site and surface- or groundwater resources. Soils

can impact site design in a variety of ways. If the soils are impermeable, groundwater

is protected from NO3 pollution, but runoff is maximized, which must be managed

to prevent BOD, P, and pathogens from entering surface waters. On the other hand,

highly permeable soils reduce the runoff potential but may allow excessive NO3

infiltration to groundwater. Intermediate soil types may be best for sites that are

operated on the native soil. For some large facilities, or those handling challenging

feedstocks, a working surface of gravel, compacted sand, oiled stone, or even asphalt

or concrete may be appropriate. Such surfaces can improve trafficability during wet

seasons, but the surface or groundwater quality issues remain.

The buffer between the site and surface- or groundwater resources is the first

line of defense against water pollution. Deep soils, well above the seasonally high

water table, can filter solid particles and minimize NO3 migration. Horizontal buffers

can filter and absorb surface runoff, and can be enhanced by specially designed grass

filter strips.

Site design issues that may impact water quality include the selection of a

working surface (native soil or an improved surface), exclusion of run-on to the site

by surface diversions, possible drainage of wet sites, and the possible provision of

roofs over some or all of the composting area to divert precipitation and to keep

compost or waste materials dry. In all but fully roofed sites, surface runoff may need

to be managed as described later. Slope of the site and surface drainage to either

divert uphill water away from the site or collect site runoff for management should

be considered in the design process.

A number of factors combine to determine the quality of water running off

compost sites. One obvious factor which is often overlooked is the excess water

running onto the site from upslope. Diversion ditches and berms that divert water

around the site minimize the runoff that needs to be managed. Siting the facility on

a soil with moderate to high permeability also significantly reduces the runoff

generated on the site. For the runoff which remains, alternatives to surface discharge



© 2001 by CRC Press LLC



include such simple technologies as soil treatment, filter strips, or recirculation, so

that sophisticated collection and treatment systems should not be needed.

These simple, low-cost treatment strategies have proven effective for a variety

of wastewaters and organic wastes (Loehr et al., 1979). Soil treatment forces the

percolation of water through the soil profile, where these organic compounds can

be adsorbed and degraded. Vegetative filter strips slow the motion of runoff water

so that many particles can settle out of the water, while others are physically filtered

and adsorbed onto plants. Recirculation involves pumping the runoff water back into

the compost windrows, where the organic compounds could further degrade and the

water would be evaporated through the composting process. This last option should

work very well during dry summer or early fall weather, when water often needs to

be added, but would not be appropriate if the moisture content of the compost was

already high.

B. Operations

The day to day operation of the composting site offers considerable opportunities

to minimize water quality impacts. The proper selection, mixing, and management

of materials can help control overall runoff, BOD, and pathogen and nutrient movement. Assuring appropriate moisture and C:N ratios throughout the composting

process can be very effective at limiting these pollutants.

NO3 is most easily controlled by maintaining an appropriate C:N ratio in the

composting mixture. Raw materials should normally be blended to approximately

30:1 or greater C:N ratio by weight. The ratio between these key elements is based

on microbial biomass and energy requirements. Inadequate N (a high C:N ratio)

results in limited microbial biomass and slow decomposition, while excess N (a low

C:N ratio) is likely to leave the composting system as either NH3 (odors) or NO3

(water pollution). In a N-limited system, microorganisms efficiently assimilate NO3,

NH3 and other N compounds from the aqueous phase of the compost, thus limiting

the pollution threat.

The ideal C:N ratio depends on the availability of these elements to microbial

decomposition. C availability is particularly variable, depending on the surface area

of particles and the extent of lignification of the material. Composting occurs in

aqueous films on the surfaces of particles, so greater surface area increases the

availability of C compounds. Lignin, because of its complex structure and variety

of chemical bonds, is resistant to decay. For both of these reasons the C in large

wood chips is less available than that in straw or paper, so greater quantities of wood

chips would be required to balance a high N source like manure.

The data from experimental studies indicate low C:N ratio mixtures can generate

NO3 levels above the groundwater standard (Cole, 1994; Rymshaw et al., 1992).

Much of this NO3 in runoff and leachate infiltrates into the ground. Although

microbial assimilation and denitrification may somewhat reduce these levels as water

passes through the soil, these processes have a limited effect and are difficult to

control. Proper management of the C:N ratio is perhaps the only practical way to

limit NO3 contamination from the site short of installing an impermeable pad and

water treatment system.

© 2001 by CRC Press LLC



The other important factor to consider when creating a composting mixture is

water content. Excess water, in addition to increasing the odor potential via anaerobic

decomposition, increases the runoff and leachate potential of a composting pile

during rainfall events.

With both C:N ratios and moisture content, the optimum water and N levels for

rapid composting may create a greater than necessary water pollution threat. Increasing the C:N ratio from 30:1 to 40:1 and decreasing the water content from 60 to

50% may slow down decomposition somewhat, but can provide an extra margin of

safety in protecting water quality.

Once the materials are mixed and formed into a compost pile, windrow management becomes an important factor. Windrows should be oriented parallel to the

slope, so that precipitation landing between the windrows can move freely off the

composting area. This will minimize windrow saturation. Pile shape can have a

considerable influence on the amount of precipitation retained in a pile, with a flat

or concave top retaining water and a convex or peaked shape shedding water,

particularly in periods of heavy rain. These effects are most pronounced when the

composting process is just starting or after a period of dry weather. In the early

phases of composting, a peaked windrow shape can act like a thatched roof or

haystack, effectively shedding water. Part of this effect is due to the large initial

particle size, and part is due to waxes and oils on the surfaces of particles. Both of

these initial effects diminish over time as the material decomposes. During dry

weather the outer surface of even stabilized organic material can become somewhat

hydrophobic, limiting absorption and encouraging runoff.

If a pile does get too moist, the only practical way to dry it is to increase the

turning frequency. The clouds of moisture evident during turning release significant

amounts of water, and the increased porosity that often results from turning increases

diffusion and convective losses of moisture between turnings. This approach can be

helpful during mild or warm weather, but caution must be exercised in winter when

excessive turning can cool the pile.

C. Runoff Management

Implementation of the preventative measures described previously can considerably reduce the water pollution threat. However, some facilities may require

additional management of runoff from the site. The runoff pollutants of primary

concern are BOD and P, largely associated with suspended solids particles. Pathogenic cysts may either be absorbed on particles or be free in solution, and the relative

significance is not adequately researched. Four readily available strategies exist to

help control these pollutants: (1) vegetative filter strips, (2) sediment traps or basins,

(3) treatment ponds, and (4) recirculation systems.

The simplest runoff management strategy is the installation of a vegetative filter

strip. Vegetative filter strips trap particles in dense surface vegetation. Grasses are

commonly used and must be planted in a carefully graded surface over which runoff

can be directed in a thin, even layer. Suspended particles flowing slowly through the

grass attach to plants and settle to the soil surface, leading to a significant reduction

in nutrients, sediment, and BOD levels (Dillaha et al., 1989; Magette et al., 1989).

© 2001 by CRC Press LLC



Sediment traps operate by settling dense particles out of the runoff. Particles

settle by gravity during passage through a basin of slowly moving water. This

approach can be particularly effective for removing P associated with sediment

(NRCS, 1992). Because much of the BOD and N in compost site runoff is associated

with light organic particles, the effectiveness of this approach may be somewhat

limited. However, it helps limit sediment movement off the site, and can be a useful

adjunct to either a vegetative filter strip or a treatment pond, enhancing the effectiveness of each.

During dry periods of the year, compost runoff can be recirculated to the compost

piles themselves, or alternately used to irrigate cropland or pasture. The nutrients

as well as moisture can thus serve a useful purpose, either by supplying needed

moisture to the compost windrows or by providing nutrients and water to crops.

However, a recirculation system requires both a pumping and distribution system

and adequate storage capacity for prolonged wet periods. Although this approach

offers a closed system, which appears ideal for pathogen control, care may need to

be taken to separate runoff from fresh feedstocks (especially manure) to avoid

contaminating finished compost or crops.

Storage requires the construction of a pond, which can also be used to treat the

waste (Figure 3.12). Ponds can be designed for aerobic or facultative treatment of

runoff water. In either case microorganisms continue the decomposition process started

in the compost pile, but in an aqueous system. As the organic material stabilizes, the

BOD levels drop. Pathogen levels are also expected to drop, although the rate depends

on seasonal temperature variations and slows during winter in unfrozen portions of a

pond. To be effective, ponds must be designed to contain the runoff from major storm

events, with an adequate residence time for microbial stabilization. Details of pond

design vary with climate, runoff characteristics, and pond effluent requirements. The

Natural Resources Conservation Service (NRCS, 1992) has considerable expertise in

adapting treatment systems to the local situation.

All these treatment options help remove N and P as well as BOD and pathogens.

Sediment basins and ponds settle out particulate matter, which includes bound

nutrients such as P. However, these sedimentation mechanisms do not remove nutrients or BOD as well as soil adsorption and crop uptake in a land treatment system.

For N removal, vegetative filter strips and irrigation systems can both be effective,

and either is enhanced by alternating flow pulses with rest periods. Phosphorus

removal is most efficient under aerobic conditions, and irrigation systems generally

show higher removal rates than vegetative filter strips, although either can be effective. Although little is currently known about the effectiveness of these approaches

in destroying the pathogens of concern, increased opportunities for adsorption,

desiccation, and other forms of environmental and microbiological stress are integral

to the physical and biological treatment processes described. An appropriate combination of these removal mechanisms can be designed to address the pollution

parameters of local concern.

Water quality protection at a composting site can be accomplished through proper

site design, operations, and runoff management. Composting facilities vary widely

in size, materials processed, and site characteristics, and all these factors will affect

the design of appropriate preventative measures. Although the available evidence is

© 2001 by CRC Press LLC



Figure 3.12



Water retention pond at a composting site. Hay bales filter out sediment in runoff.



limited, current indications are that runoff from composting windrows has BOD and

nutrient levels comparable to low-strength municipal wastewaters. Land treatment

systems that have proven effective for these other wastewaters are likely to be

effective for windrow composting facilities as well.



REFERENCES

Alix, C.M. 1998. Retrofits curb biosolids composting odors. BioCycle 39(6):37–39.

BioCycle. 1989. The BioCycle Guide to Yard Waste Composting. JG Press, Emmaus, Pennsylvania.

Brown K.H., J.C. Bouwkamp, and F.R. Gouin. 1998. The influence of C:P ratio on the

biological degradation of municipal solid waste. Compost Science and Utilization

6(1):53–58.

Bundy, D.S. and S.J. Hoff. 1998. The testing procedures and results of pit additives tested at

Iowa State University, p. 270–282. In: C. Scanes and R. Kanwar (eds.). Animal Production Systems and the Environment: An International Conference on Odor, Water Quality,

Nutrient Management and Socioeconomic Issues. Proceedings Volume 1: Oral Presentations.

CIWMB (California Integrated Waste Management Board). 2000. California Code of Regulations, Title 14, Division, 7, Chapter 3. Website: http://www.ciwmb.ca.gov/Regulations/Title 14/default.htm. Verified 24 June 2000.

Citterio, B., M. Civilini, A. Rutili, A. Pera, and M. de Bertoldi. 1987. Control of a composting

process in bioreactor by monitoring chemical and microbial parameters, p. 633–642. In:

M. de Bertoldi, M.P. Ferranti, P. L’Hermite, and F. Zucconi (eds.). Compost: Production,

Quality and Use. Elsevier Applied Science, London, United Kingdom.

Cole, M.A. 1994. Assessing the impact of composting yard trimmings. BioCycle 35(4):92–96.

© 2001 by CRC Press LLC



Croteau, G., K. May, and M. Schaan. 1996. Costs and benefits of on-site organics composting.

BioCycle 37(5):65–68.

Das, K. and H.M. Keener. 1996. Process control based on dynamic properties in composting:

moisture and compaction considerations, p.116–125. In: M. de Bertodli, P. Sequi, B.

Lemmes, and T. Papi (eds.). The Science of Composting. Blackie Academic & Professional, London, United Kingdom.

Diaz, L.F., G.M. Savage, and C.G. Golueke. 1982. Resource Recovery from Municipal Solid

Wastes — Volume 1, Primary Processing. CRC Press, Boca Raton, Florida.

Dickson, N., T.L. Richard, and R.E. Kozlowski. 1991. Composting to Reduce the Waste

Stream: A Guide to Small Scale Food and Yard Waste Composting. Natural Resource,

Agriculture, and Engineering Service (NRAES), Ithaca, New York.

Dillaha, T.A., R.B. Reneau, S. Mostaghimi, and D. Lee. 1989. Vegetative filter strips for

agricultural nonpoint source pollution control. Transactions of the American Society of

Agricultural Engineers 32(2):513–519.

Dougherty, M. (ed.). 1999. Field Guide to On-Farm Composting. Natural Resource, Agriculture, and Engineering Service (NRAES), Ithaca, New York.

Dunson, J.B., Jr. 1993. Control of odors by physical-chemical approaches, p. 242–261. In:

H.A.J. Hoitink and H. Keener (eds.). Science and Engineering of Composting: Design,

Environmental, Microbiological, and Utilization Aspects. Renaissance Publications,

Worthington, Ohio.

Eitzer, B.D. 1995. Emissions of volatile organic chemicals from municipal solid waste composting facilities. Environmental Science and Technology 29(4):896–902.

Epstein, E. 1997. The Science of Composting. Technomic Publishing, Basel, Switzerland.

Finstein, M.S. and J.A. Hogan. 1993. Integration of composting process microbiology, facility

structure and decision making, p. 1–23. In: H.A.J. Hoitink and H. Keener (eds.). Science

and Engineering of Composting: Design, Environmental, Microbiological, and Utilization Aspects. Renaissance Publications, Worthington, Ohio.

Finstein, M.S., J. Cirello, S.T. MacGregor, F.C. Miller, and K.M. Psarianos. 1980. Sludge

Composting and Utilization: Rational Approach to Process Control. US-EPA Project C340-678-01-1. Accession No. PB82-13623, National Technical Information Service,

Springfield, Virginia.

Finstein, M.S., F.C. Miller, P.F. Strom, S.T. MacGregor, and K.M. Psarianos. 1983. Composting ecosystem management for waste treatment. Bio/Technology 1:347–353.

Finstein, M.S., F.C. Miller, F.C. MacGregor, and K.M. Psarianos. 1985. The Rutgers Strategy

for Composting: Process Design and Control. Rutgers University, New Brunswick, New

Jersey.

Finstein, M.S., F.C. Miller, and P.F. Strom. 1986. Waste treatment composting as a controlled

system, p. 362–398. In: H.J. Rehm and G. Reed (eds.). Biotechnology: A Comprehensive

Treatise in 8 Volumes – Volume 8: Microbial Degradations. VCH Verlagsgesellschaft,

Weinheim, Federal Republic of Germany.

Finstein, M.S., F.C. Miller, J.A. Hogan, and P.F. Strom. 1987a. Analysis of EPA guidance on

composting sludge. Part I: biological heat generation and temperature. BioCycle

28(1):20–26.

Finstein, M.S., F.C. Miller, J.A. Hogan, and P.F. Strom. 1987b. Analysis of EPA guidance on

composting sludge. Part II: biological process control. BioCycle 28(2):42–47.

Finstein, M.S., F.C. Miller, J.A. Hogan, and P.F. Strom. 1987c. Analysis of EPA guidance on

composting sludge. Part III: oxygen, moisture, odor, pathogens. BioCycle 28(3):38–44.

Goldstein, N. and K. Gray. 1999. Biosolids composting in the United States. BioCycle

40(1):63–75.



© 2001 by CRC Press LLC



Golueke, C.G. 1972. Composting: A Study of the Process and Its Principles. Rodale Press,

Emmaus, Pennsylvania.

Gray, K.R. and A.J. Biddlestone. 1974. Decomposition of urban waste, p. 743–775. In: C.H.

Dickinson and G.J.F. Pugh (eds.). Biology of Plant Litter Decomposition,Volume 2.

Academic Press, London, United Kingdom.

Haug, R.T. 1993. The Practical Handbook of Compost Engineering. CRC Press, Boca Raton,

Florida.

Hay, J.C. and R.D. Kuchenrither. 1990. Fundamentals and applications of windrow composting. Journal of Environmental Engineering 116:746–763.

Higgins, A.J., V. Kasper Jr., D.A. Derr, M.E. Singley, and A. Singh. 1981. Mixing systems

for sludge composting. BioCycle 22(5):18–22.

Hoitink, H.A.J., M.J. Boehm, and Y. Hadar. 1993. Mechanisms of suppression of soilborne

plant pathogens in compost, p. 601–621. In: H.A.J. Hoitink and H. Keener (eds.). Science

and Engineering of Composting: Design, Environmental, Microbiological, and Utilization Aspects. Renaissance Publications, Worthington, Ohio.

Horwath, W.R., L.F. Elliot, and D.B. Churchill. 1995. Mechanisms regulating composting of

high carbon to nitrogen ratio grass straw. Compost Science and Utilization 3(3):22–30.

JG Press, Inc. 1986. The BioCycle Guide to In-Vessel Composting. Emmaus, Pennsylvania.

Kuter, G.A. (ed.). 1995. Biosolids Composting. Water Environment Federation, Alexandria,

Virginia.

Lafrance, C., P. Lessard, and G. Buelna. 1996. Évaluation de la filtration sur tourbe et compost

pour le traitmement de l’effluent d’une usine de compostage de résidus verts. Canadian

Journal of Civil Engineering 23:1041–1050.

Lenton, T.G. and E.I. Stentiford. 1990. Control of aeration in static pile composting. Waste

Management Research 8:299–306.

Lesson, G. and K.A.M. Winer. 1991. Biofiltration: An innovative air pollution control technology for VOC emissions. Journal of the Air and Waste Management Association

41(8):1045–1054.

Loehr, R.C., W.J. Jewell, J.D. Novak, W.W. Clarkson, and G.S. Friedman. 1979. Land Application of Wastes, Volume II. Van Nostrand Reinhold, New York.

Lopez-Real, J. and M. Baptisa. 1996. A preliminary study of three manure composting systems

and their influence on process parameters and methane emissions. Compost Science and

Utilization 4(3):71–82.

Lorig, T.S. 1992. Cognitive and noncognitive effects of odour exposure; electrophysiological

and behavioural evidence, p. 161–173. In: S. Van Toller and G.H. Dodd (eds.). The

Psychology and Biology of Perfume. Elsevier Applied Science, London, United Kingdom.

Ludvigson, H.W. and T.R. Rottman. 1989. Effects of ambient odors of lavender and cloves

on cognition, memory, affect and mood. Chemical Senses 14:525–536.

Lynch, J.M. 1993. Substrate availability in the production of composts, p. 24–35. In: H.A.J.

Hoitink and H. Keener (eds.). Science and Engineering of Composting: Design, Environmental, Microbiological, and Utilization Aspects. Renaissance Publications, Worthington, Ohio.

Lynch, N. J. and R.S. Cherry. 1996a. Design of passively aerated compost piles: vertical air

velocities between pipes, p. 973–982. In: M. de Bertodli, P. Sequi, B. Lemmes, and T.

Papi (eds.). The Science of Composting. Blackie Academic & Professional, London,

United Kingdom.

Lynch, N. J. and R.S. Cherry. 1996b. Winter composting using the passively aerated windrow

system. Compost Science and Utilization 4(3):44–52.



© 2001 by CRC Press LLC



Magette, W.L., R.B. Brinsfield, R.E. Palmer, and J.D. Wood. 1989. Nutrient and sediment

removal by vegetated filter strips. Transactions of the American Society of Agricultural

Engineers 32(2):663–667.

Massachusetts Department of Environmental Protection. 1988. Leaf Composting Guide. Boston, Massachusetts.

Mathur, S.P. 1995. Natural aeration static pile (based on Agriculture Canada’s PAWS technology). In: Composting Technologies and Practices – A Guide for Decision Makers.

The Composting Council of Canada, Ottawa, Ontario, Canada.

Mathur, S.P. 1997. Composting processes, p. 154–196. In: A.M. Martin (ed.). Bioconversion

of Waste Materials to Industrial Products. Blackie Academic and Professional/Chapman

& Hall, London, United Kingdom.

Mathur, S.P. and R.W. Richards. 1999. Large-scale generation of hygenic, high-quality compost from beef feedlot manure and sawmill residues in natural aeration static piles

(NASP) without pipes, plenums or envelope, p. 36. In: P. Warman and T. R. MunroWarman (eds.). Abstracts of the International Composting Symposium, September, 1999.

Coastal BioAgresearch, Ltd., Truro, Nova Scotia, Canada.

Mathur, S.P., N.K. Patni, and M.P. Levesque. 1988. Composting of Manure Slurries with Peat

Without Mechanical Aeration. Canadian Society of Agricultural Engineers, Annual Conference Paper No. 88–123. 13 pages.

Mathur S.P., N.K. Patni, and M.P. Levesque. 1990. Static pile, passive aeration composting

of manure slurries using peat as a bulking agent. Biological Wastes 34:323–333.

McCartney, D.M. and H. Chen. 1999. Physical modeling of composting using biological load

cells: effect of compressive settlement on free air space and microbial activity, p. 37. In:

P. Warman and T. R. Munro-Warman (eds.). Abstracts of the International Composting

Symposium, September, 1999. Coastal BioAgresearch, Ltd., Truro, Nova Scotia, Canada.

Michel, F.C., Jr., L.J. Forney, A. J.-F. Huang, S. Drew, M. Czuprenski, J.D. Lindeberg, and

C.A. Reddy. 1996. Effects of turning frequency, leaves to grass ratio, and windrow vs.

pile configuration on the composting of yard trimmings. Compost Science and Utilization

4(1):26–43.

Miller, F.C. 1991. Biodegradation of solid wastes by composting, p. 1–31. In: A.M. Martin

(ed.). Biological Degradation of Wastes. Elsevier Applied Science, London, United

Kingdom.

Miller, F.C. 1993. Minimizing odor generation, p. 219–241. In: H.A.J. Hoitink and H. Keener

(eds.). Science and Engineering of Composting: Design, Environmental, Microbiological,

and Utilization Aspects. Renaissance Publications, Worthington, Ohio.

Miner, R.J. 1995. A Review of the Literature on the Nature and Control of Odors from Pork

Production Facilities. National Pork Producers Council, Des Moines, Iowa.

Natural Resources Conservation Service (NRCS). 1992. National Engineering Handbook Part

651: Agricultural Waste Management Field Handbook. U.S. Department of Agriculture

(USDA), Washington, DC. http://www.ftw.nrcs.usda.gov/awmfh.html. Verified 24 June

2000.

Naylor, L.M. 1996. Composting, p. 193–269. In: M.J. Girovich (ed.). Biosolids Treatment

and Management: Processes for Beneficial Use. Marcel Dekker, New York.

Panter, K., R. DeGarmo, and D. Border. 1996. A review of features, benefits and costs of

tunnel composting systems in Europe and in the USA, p. 983–986. In: M. de Bertodli,

P. Sequi, B. Lemmes, and T. Papi (eds.). The Science of Composting. Blackie Academic

& Professional, London, United Kingdom.

Patni, N. 2000. Videotape interview. In: R. Rynk (producer). The Future of Agricultural

Composting, A Video Workshop. Compost Education and Resources for Western Agriculture, University of Idaho, Moscow, Idaho.

© 2001 by CRC Press LLC



Poincelot, R.P. 1975. The Biochemistry of Composting. The Connecticut Agricultural Experiment Station, New Haven, Connecticut.

Randle, P. and P.B. Flegg. 1978. Oxygen measurements in a mushroom compost stack. Scientia

Horticulturae 8:315–323.

Richard, T.L. 1992. Municipal solid waste composting: physical and biological processing.

Biomass and Bioenergy 3(3-4):163–180.

Richard, T.L. 1997. Course notes on composting aeration design. http://www.ae.iastate.edu/

Ae573_ast475/composting-aeration_design_not.htm

Richard, T.L. and M. Chadsey. 1994. Environmental impact assessment, p. 232–237. In:

BioCycle staff (eds.). Composting Source Separated Organics. J.G. Press, Emmaus,

Pennsylvania. Also published in 1990 as: Environmental monitoring at a yard waste

composting facility. BioCycle 31(4):42–46.

Richman, B. and R. Rynk. 1994. Recycling Yard Debris. Panhandle Health District, Couer

d’Alene, Idaho.

Ritter, W.F. 1981. Chemical and biochemical odor control of livestock wastes: A review.

Canadian Agricultural Engineering 23:1–4.

Rymshaw, E., M.F. Walter, and T.L. Richard. 1992. Agricultural Composting: Environmental

Monitoring and Management Practices. Department of Agricultural and Biological Engineering, Cornell University, Ithaca, New York.

Rynk, R. 1994. Composting equipment, p. 147–179. In: C.W. Heuser and P.E. Heuser (eds.).

Recycling and Resource Conservation, A Reference Guide for Nursery and Landscape

Industries. Pennsylvania Nurserymen’s Association, Harrisburg, Pennsylvania.

Rynk, R. 2000a. Fires at composting facilities: Part I. BioCycle 41(1):54–58.

Rynk, R. 2000b. Fires at composting facilities: Part II. BioCycle 41(2):58–62.

Rynk, R. 2000c. Review of contained composting systems: Part I. BioCycle 41(3):30–36.

Rynk, R. 2000d. Review of contained composting systems: Part II. BioCycle 41(4):67–72.

Rynk, R.F., M. van de Kamp, G.B Willson, M.E. Singley, T.L. Richard, J.J. Kolega, F.R.

Gouin, L.L. Laliberty, D. Kay, D.W. Murphy, H.A.J. Hoitink, and W.F. Brinton. 1992.

On-Farm Composting Handbook. Natural Resource, Agriculture, and Engineering Service (NRAES), Ithaca, New York.

Schiffman, S.S., E.A. Sattely Miller, M.S. Suggs, and B.G. Graham. 1995. The effect of

environmental odors emanating from commercial swine operations on the mood of

nearby residents. Brain Research Bulletin 37(4):369–375.

Schoenecker, B. and A. McConnell. 1993. Composting yard waste under cover and over air.

BioCycle 34(1):44–45.

Shoda, M. 1991. Methods for the biological treatment of exhaust gases, p. 1–30. In: A.M.

Martin (ed.). Biological Degradation of Wastes. Elsevier Applied Science, London,

United Kingdom.

Singley, M., A. J. Higgins, and M. Franklin-Rosengaus. 1982. Sludge Composting and Utilization — A Design and Operating Manual. Rutgers University, New Brunswick, New

Jersey.

Stentiford, E.I. 1996. Composting control: principles and practice, p. 49–59. In: M. de

Bertodli, P. Sequi, B. Lemmes, and T. Papi (eds.). The Science of Composting. Blackie

Academic & Professional, London, United Kingdom.

Stentiford, E.I. and T.J. Pereira Neto. 1985. Simplified systems for refuse/sludge compost.

BioCycle 26(5):46–49.

Strom, P.F. and M.S. Finstein. 1985. Leaf Composting Manual for New Jersey Municipalities.

Rutgers University, New Brunswick, New Jersey.

The Compost Council. 1994. Compost Facility Operating Guide. Alexandria, Virginia.



© 2001 by CRC Press LLC



United States Environmental Protection Agency (U.S. EPA). 1985. Composting of Municipal

Wastewater Sludges. EPA/625/4-85-016. Office of Wastewater Management, Cincinnati,

Ohio.

United States Environmental Protection Agency (U.S. EPA). 1994. In-Vessel Composting of

Municipal Wastewater Sludge. EPA/625/8-89/016. Office of Wastewater Management,

Cincinnati, Ohio.

Williams, T.O. and F.C. Miller. 1993. Composting facility odor control using biofilters, p.

262–281. In: H.A.J. Hoitink and H. Keener (eds.). Science and Engineering of Composting: Design, Environmental, Microbiological, and Utilization Aspects. Renaissance

Publications, Worthington, Ohio.

Willson, G.B. 1980. Manual for Composting Sewage Sludge by the Aerated Static Pile Method.

U.S. Environmental Protection Agency (U.S. EPA), Cincinnati, Ohio.

Willson, G.B., J.F. Parr, and J.L. Thompson. 1979. Evaluation of mixers for blending sewage

sludge with wood chips, p. 48–54. In: Municipal and Industrial Sludge Composting.

Information Transfer Inc., Rockville, Maryland.



© 2001 by CRC Press LLC



CHAPTER



4



Compost Quality Attributes,

Measurements, and Variability

Dan M. Sullivan and Robert O. Miller



CONTENTS

I.

II.

III.

IV.



V.



VI.



What is Compost Quality?

Compost Quality Specifications or Guidelines

Compost Sampling

Physical Properties of Composts

A. Moisture Content

B. Bulk Density

C. Water-Holding Capacity

D. Particle Size and Man-Made Inerts

Chemical Properties of Composts

A. Total Organic Carbon (C)

B. Volatile Solids (Volatile Organics)

C. Cation Exchange Capacity

D. Total Nitrogen (N)

E. Inorganic Nitrogen (N)

F.

Acidity/Alkalinity (pH)

G. Electrical Conductivity (Soluble Salts)

H. Phosphorus (P), Potassium (K), Calcium (Ca),

Magnesium (Mg), and Micronutrients

Evaluating Compost Maturity and Stability

A. Sensory Indicators of Maturity

B. Chemical Indicators of Maturity

1. Organic Matter

2. Carbon and Nitrogen

C. Compost Stability as a Maturity Indicator



© 2001 by CRC Press LLC